文献类型：期刊文献

英文题名："Ion-cage" structure of graphene oxide membranes with stable interlayer spacings towards efficient desalination

作者：Wang, Shuai[1];Yi, Ruobing[2];Huang, Yi[3];Zuo, Haoran[4];Zhang, Yangtian[5];Huang, Yingying[1];Chen, Liang[6];Liang, Shanshan[1]

机构：[1]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China;[2]Xi An Jiao Tong Univ, Sch Phys, MOE Key Lab Nonequilibrium Synth & Modulat Condens, Xian 710049, Peoples R China;[3]Zhejiang A&F Univ, Coll Optomech Engn, Hangzhou 311300, Peoples R China;[4]Southwest Petr Univ, Sch Chem & Chem Engn, Oil & Gas Appl Chem Key Lab Sichuan Prov, Chengdu, Sichuan, Peoples R China;[5]Zhejiang A&F Univ, Coll Carbon Neutral, Coll Environm & Resources, Hangzhou 311300, Peoples R China;[6]Ningbo Univ, Sch Phys Sci & Technol, Ningbo 315211, Peoples R China

年份：2024

卷号：336

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20240315399604);WOS:【SCI-EXPANDED(收录号:WOS:001168663000001)】；

基金：This work was supported by the National Natural Science Foundation of China (12004110, 11974366, and 12004109) , and the Fundamental Research Funds for the Central Universities. The authors thank the staff members from the BL06B beamline of Shanghai Synchrotron Radiation Facility (SSRF) for assistance during data collection.

语种：英文

外文关键词：Desalination - Electrostatics - Graphene - Magnesium compounds - Microfiltration - Nanofiltration membranes - Sodium chloride - Sodium sulfate - Sulfur compounds - Water filtration

摘要：Multilayered graphene oxide (GO) membrane with sub-nanometer channels is an ideal candidate for desalination. However, excluding small ions using GO-based membranes in the pressured filtration processes remains a great challenge due to the tortuous transport paths of laminates and their water-swelling characteristic. In our previous work, we developed the cation-controlled theory to precisely regulate the interlayer spacing of GO membranes in aqueous solutions. In this work, we proposed an "ion-cage" strategy to enhance the stability (anti-swelling) of the K-controlled GO (icGO-K) membrane for achieving efficient desalination. The icGO-K membrane, coated with positively charged polyethyleneimine (PEI) on its upper and lower surfaces, immobilized intercalated cation K+ between the laminates by electrostatic repulsion to maintain the stability of the confined interlayer spacing. The icGO-K membrane demonstrated superior rejection of 95.3 %, 83.2 %, 81.8 %, and 70.7 % for MgCl2, MgSO4, NaCl, and Na2SO4 while maintaining competitive permeance of similar to 3.5 L m(-2)h(-1) bar(-1) in the desalination process. More importantly, the icGO-K membrane exhibited ultra-long desalination stability up to 720 h. The enhanced performance can be attributed to the synergistic effect of the confined interlayer spacing and surface electrostatic repulsion. Overall, this work provides attractive strategy to fabricate fine-tuning 2D laminate nanochannels for high efficiency of desalination application.